Junction-box.



NO- 830,316. PATENTED SEPT. 4, 1906.

E. 'I'. GREENFIELD.

JUNCTION BOX.

APPLICATION FILED 00T.10. 1904.

lated cables and the means for securing ITED STATES PATENT onirica.

Specification of Letters Patent.

Patented Sept. 4, 1906.

Application filed October 10.1904. Serial 110.227.866.

whereby the ends of armored conduits or cables may be secured to ametallic junctionbox by clampin the same against one of the inner wallsor means being located wholly within the box and readily accessible whenthe parts are bein g put together.

In prior patents granted to me on the 12th day of June, 1900, andnumbered 651,484,l

and January 8, 1901, numbered 665,676, I have disclosed two-partjunction-boxes in which the ends of armored conduits are adapted to beheld between theparts of a two-part box and rigidly secured to one partby means located wholly within the box, and the present invention is animprovement upon the inventions disclosed in the beforementioned patentsin that the box in the resent instance is substantially a dustproof boxand is provided with openings in its sides for the reception of theconduits, the latter being secured to the interior thereof by clampingmeans which is readily accessible when theconduits or cables and the boxarebeing united.

For a full and clear understanding of my invention,rsuch as will enableothers skilled in the art to construct and use the same, reference ishad to the accompanying drawings, in which- Fi ure 1 is a plan view ofmy novel junction-Iiox provided with my improved means for securing theends of inleading armored conduits thereto, and Fig. 2 is a transversesectional view taken through Fig. 1 on thev line X X and as seen lookingthereatfrom left to right in the direction of the arrows, the armoredconduits and their inclosed inslilit e same to the box being shown inelevational View.

Referring to the drawings in detail, 1 1 represent the two sides andbottom of a junction-box bent in U. form of one piece of aces thereof,said clamping` relatively thin exible metal, such as sheetiron, and 2 2the ends thereof secured to the former by bent-over lu s or ears 3 3 3and rivets in a manner whic will be obvious on inspection of thedrawings.

4 4 4 4 4 4 represent horizontally-disposed lugs or ears integral withthe ends 2 2 and located at the upper end of the box when completed,their function being to secure the junction-box either to a ceiling, awall, or'

other point of support by screws extending therethrough. In theconstruction of such a box the sides and bottom are bent in U form inthe manner described and the ends 2 2 are struck up with the respectivesets of lugs or ears 3 3 and 4 4 bent 1n opposite directions, theinleading holes or openings 5 5 5 for the conduits being punched orstruck out at the same operation and of the proper diameter to receivethe inleading ends of armored conduits or cables 6 6 6.

7 7 are metal clamps, the same being provided in one instance with ahole in its middle, as shown in Fig. 2, for receiving Aa clamping-screw8 and adapted to bearat its opposite ends upon the ends of two inleadingconduits, and in the other instance with a downwardly-extending leg 9the screw 8 being located between said leg and the bearing ory clutchingend of the clamp.

In Wiring a building the parts are put together as follows: The ends ofthe armored conduits or cables 6 6 6 are inserted through the openings 55 within the box to a proper distance, as shown, andthe clamps 7 areplaced in osition so as to bear upon them, either dou ly, as shown atthe right of Fig. 1 and in elevational view in Fig. 2, or singly, asshown at the left of Fig. 1. The clamping screws 8 are then secured inplace through the bottom of the box in the mannerI shown and so as toeectually grip or hold the parts to ether. The Wiring of the conductorsin t e box is then effected in the usual manner, and it is securedeither to the ceiling, side wall, or other point of support by screwsextending through the lugs or ears 4 4 4 on each side.

I am aware that metallic 'unction-boxes have heretofore been made ybending or joiningstrips of sheet metal into U form and uniting theedges thereof together by a seam or by rivets, the ends being similarlysecured; but am not aware that any one has heretofore constructed ajunction-box in the manner hereinbefore described by joining three IOOIIO

one surface of the pieces of sheet metal together through the agency oflugs or ears upon two of the pieces and rivets passing through said lugsor ears and the three pieces. I am also aware that various means haveheretofore been utilized for effecting the union between the inleadingends of armored conduits or cables and j unction-boxes, both in thenature of set-screws, clamping or clutching means, &c., and I make noclaim hereinafter broad enough to include generically such structuraldevices, my most eneric claim being to means located whol ywithin thebox and in such manner as to be wholly concealed therein and to effect asecure mechanical union between the ends of the conduits and theinterior of the box with which they are connected, the same bem soarranged as to be readily accessible 1n a ox of any depth or of varyingproportions after it has been put in place on the wall or ceiling, theclam ing effect being between gox'and clamping means which receives theends of the conduits between it and the box, such an arrangement makingit practically impossible for unauthorized persons to interfere'ortamperwith the interconnecting means and also consti tuting a simple,neat, and efIicient union of' the parts which are wholly concealedwithin the box.

-.I am aware that a junction-box for electric house-conduits hasheretofore been devised 1n which inleading conduits are secured inOpenings in the ends ofthe box by a duplex clamp resting upon the endsof the conduits and secured internally to the end of the box by a screwhaving an inclined head extending through an opening in the middle ofthe clamp. With such an arrangement,

owever, where the-conduit-boxes are of considerable depth, it is notpossible to secure the box first to the wall or ceiling and thenadjustably secure the clamp against the ends ofthe conduits. Myinvention makes it possible to 'accomplish this result with boxes of anydepth, thereby enabling a constructor to first secure the ]unctionboxesat various points and afterward effect a permanent union between them,and in this important feature is found the essence of my invention.`

Having thus described my invention, what I claim, and desire to secureby Letters Patent of the United States, is*

1. A junction-box provided with inleading i and into thebefore-mentioned screw-threaded opening in the" bottom.

2. A junction-box provided with pairs of conduit-openings extendin intothe same at pointsrelatively near its ottom; a screwthreaded openinglocated in the bottom of the box between each of the before-mentionedopenings; a clamp adapted to extendl laterally over each pair ofopenings and a screw adapted to extend through the clamp and into thescrew-threaded opening. y

3. A junction-box constructed of three pieces of sheet metal, one piececonstituting the bottomrand sides thereof and the other two pieces theends; said ends being provided with integral lugs secured to the bodypart of the box, ,and additional integral lugs for securing the bottomof the box against a ceiling or wall; conduit-openings extending intothel box at points relatively near its bottom, in combination withscrew-threaded openings in the bottom of the box adjacent to theconduit-openings and a clamp adapted to extend laterally over eachopening andprovided with a screw adapted to be secured in place throughthe clamp and in the corresponding screw-hole in the bottom of the box,whereby all of said parts may be readily secured permanently inposition.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

' EDWIN T. GREENFIELD.

Witnesses:

C. J. KINTNER, M. F. KEATING.

